What is known about the emergency landing is that the cockpit display showed that the aircraft was having battery problems. Presumably, after the battery fire in Boston, pilots were taking no chances and landed the aircraft as soon as possible.

The batteries in these aircraft are especially important because the 787 Dreamliner fleet uses electrical systems rather than hydraulic systems found on most passenger aircraft.

After these issues, all 24 of the Boeing 787 Dreamliner aircraft operated in Japan by ANA and Japan Airlines have been grounded for safety checks. ANA owns 17 of the 24 aircraft with Japan Airlines owning the remainder. These 24 aircraft are nearly half of the 50 787 Dreamliners that have been delivered and flown commercially around the world.

In response to the issues with the aircraft, the FAA has launched a comprehensive safety review of 787 Dreamliner’s critical systems. This review will include an evaluation of how Boeing designs, manufacturers, and assembles the aircraft. Boeing has pledged to fully participate in review stating that it believes the process would bolster public confidence in the aircraft.

Considering there's, what, only 50 planes delivered to date? The FAA obviously skimped on its certification to ensure Boeing could get to market before it was possible to properly certify it without special treatment. Sounds like there is a conflict of interest at the FAA or undue political pressure being applied...

"So, I think the same thing of the music industry. They can't say that they're losing money, you know what I'm saying. They just probably don't have the same surplus that they had." -- Wu-Tang Clan founder RZA